Compressor



Nov. 13, 1928.

J. R. REPLOGLE COMPRES SOR Filed May 21, 1926 2 Sheets-Sheet 1 attonseq Nov. 13, 1928. 1,691,305

J. R. REPLOGLE COMPRES SOR Filed May 21, 1926 2 Sheets-Sheet 2 Patented Nov. 13, 1928.

UNITED STATES PATENT OFFICE.

JOHN R. REPLOGLE, or DETROIT, MICHIGAN, ASSIGNOR, BY MESNE assremmn'rs,

TO ELECTRIC REFRIGERATION CORPORATION,

RATION OF MICHIGAN.

OF DETROIT, MICHIGAIF, A CORPO- COMPRESSOR.

Application filed m 21,

This invention relates to compressors and has special reference to outlet valve structures for compressors employed with refrigerating apparatus, although not restricted to such use.-

It is common practice to provide exhaust valve structu-res,foi' compressors in which a resiliently mounted pressure resisting stop member is associated with a valve closure member so as to limit the lifting movement below a predetermined pressure and to permit an increased lifting movement above the predetermined pressure. Such structure is especially advantageous in systems in which liquid particles of refrigerant and lubricant are sometimes carried with gas which is being compressed, as the valve will operate to permit such particles to pass through the exhaust port without causing a pressure to be built up which would disturb the normal functioning of the compressor.

The outlet valve structure of compressors employed with refrigerating systems is usually arranged directly in open communication with a condenser chamber, so that the condensed refrigerant and lubricant are in contact with the exterior surfaces thereof and provide a liquid seal. The lubricant and refrigerant travel in a closed circuit through the refrigerating system and foreign matter, such as sand from the castings, or dirt, is free to travel therewith and will at times become lodged between the valve closure member and the stop member preventing a normal opening lift of the valve closure member. The valve closure movement is small under normal conditions, and any limitation in its 0 ening movement, or variation in its spec of movement, will materially reduce theefficiency of the com-' pressorand likewise system.

An object of this invention is to provide an outlet valve structure for the compressor in a refrigerating system in which foreign that of the refrigerating anatter travelling with the refrigerant and lubricant will be excluded from the space between the contacting surfaces of a'valve closure'element and a. stop member therefor. A further object of the invention is to provide an outlet valve structure for the compressor in a refrigerating system in 1926. Serial No. 110,616.

ber of a refrigerating system; Figure 2 is a fragmentary plan view of the compressor illustrating the cylinder head; Figure 3 is an enlarged sectional view through the cylinder head taken on line 3--3 of Figure 2; and Figure 4 is a sectional view taken on line 4-4 of Figure 3 showing the valve engaging face of the stop member.

Referring to the drawings by characters of reference, 10 represents the cylinder of a compressor which is provided with a flange 11 seated upon and secured to the wall 12 of a-crank case. I A compressor head is secured to the upper end of the cylinder by cap screws 14 and my improved exhaust valve structure is associated therewith. A dome 15 extends over the cylinder head and around the cylinder, and is provided with a base flange 16 which is secured in leak proof relation upon the wall 12of the crank case. The space within the dome surrounding the crank case provides a condenser chamber. for the compressed refrigerant gas passing through the cylinder head from the compressor, and suitable water circulating tubes 9 can be used within the chamber for condensing the compressed refrigerant gas in the chamber. A piston 17 is reciprocated in the cylinder by a suitable source of power, and a valve 18 is provided in the piston head through which the refrigerant gas will pass on the down stroke of the piston. It will be understood that refrigerant gas passes from the crank case, is compressed into the condenser chamber from which it flows in liquid form to an evaporator and thence hack to the crank case in gaseous condition. This type of refrigeration system is well known and a further description is therefore deemed unnecessary. The cylinder head is formed with a base flanged portion 13 from which a central annular body portion 19 extends. The central body of the head is counter-bored at its upper portion to provide a hearing 20 in which the valve closure member 21 is slidably mounted. An annular inlet port 22 of smaller diameterthan the valve seat is formed in the base of the cylinder head and is located coaxial with the counterhore. The inlet port is enlarged as it extends upwardly 1n the head and increases in diameterso that it is larger than the counter bore with which it merges at its upper end. The lower face 23 of the port interior of the bottom of the head is formed to slope upwardly and provides a seat with which a similarly extending beveled wall 24. of the valve closure member seats. A plurality of outlet ports 25 extend vertically through the upper portion of the central body portion 19 of the head, exteriorly of the counterbore, and are in open communication with the inlet port 22 at their lower ends and with the condenser chamber at their upper ends.

The valve closure element 21 comprises a cylindrical sleeve which is arranged to slide in the counter-bore 20, the upper end of the element being open, and the lower end thereof merging into the annular beveled face 23 which is closed by the wall 26.

A bracket 27 extends across the upper end of the central body of the cylinder head and is secured thereagainst by cap screws 28, a suitable lock plate 29 being provided to prevent the screws from working loose. A stop member extends into the hollow valve closure element and consists of an annular contact head 30 and a shank 31 which is slidably mounted through an, aperture 32 in the bracket. A pair of nuts 33 are screwed upon the threaded end of the shank 31 against thebracket to space the valve contact face 34 of the stop head from the inner face of the valve closure wall 26.

Associated with the head of the stop member within the valve closure member, 1 provide a thimble like member which serves to provide a dashpot 35 between the head of the stop member. and the end wall of the valve closure member. The thimble member is formed preferably of two sheet metal elements, the outer one of which is bent to provide an upper upstanding annular portion 36 and a lower depending longer annular portion 38 of smaller diameter thanthe upper portion, such annular portions being connected by a transversely extending wall 37. The inner thimbleelement is bent in a similar manner with upper and lower annular portions 39 and 41 of substantially equal length and are joined by a transverse wall extending inwardly beyond the wall 38 of the outer member. The wall 39 of the inner element fits against the Wall 36 of the outer element and is secured therewith by welding or some similar suitable means.

A bearing member consisting of a hub portion 42 and a flange 43 is slidably mounted on the stem of the stop member beneath the bracket 27 and the outer end thereof is channeled to provide a seat 44 for one end of a helical tension spring 45. The lower convolution of the spring 45 fits tightly Within the wall 39 of the inner element of the thimble and bears against the wall 41 to maintain the thimble tightly against the wall 26 of the valve closure element. A helical spring 46 having a greater tension than the spring 45 encircles the stem of the stop member and bears against the flange 43 of the bearing member and the upper wall of the head of the stop member. The upper face or the head of the stop member is provided with an annular groove 47 within which the lower edge of the wall 41 of the inner element of the thimble member extends.

The nuts 33 are adjusted to provide the desired clearance between the contact face 34 of the stop head and the adjacent end wall of the valve closure member to permit the desired charge to efliciently pass through the port 22 and ports 25 intothe condenser chamber upon each compression stroke of the compressor piston. The springs 45 and 46 exert difi'erent pressures so that until a pressure-greater than that required to normally lift the valve closure element is exerted the stop member will limit the lift of the valve closure element and upon a greater pressure being exerted against the valve closure member, due tothe pressure of liquid refrigerant or lubricant particles in the gasch'arge, the stop member will be lifted with the valve closure member and thus permit sufiicient opening to receive the entire charge above the piston.

The condensed refrigerant and lubricant oil in .the condenser chamber will fall into the open end of the valve closure member 21 the stop member under the wall 41 of the inner thimble element and across the groove 47 into the space intermediate the thimble, the head of the stop member and the adjacent end wall of the valve closure member. This confined liquid provides a dashpot effect which,-togethcr with the tension of the spring 45 against the thimble and valve closure member, serve as a shock absorber for the valve closure member and will prevent vibration thereof against the stop member. thereby eliminating chattering and loss of etliciency which would otherwise cause a reduced pumping rate. It will be seen that the thimble member serves" as a bearing for the spring 45 and also provides a dashpot which eliminates vibration noise.

and will flow over the top of the head of I member and the valve closure member, the

lift of the valve will bereduced and limit the lift 'suificiently to effect incomplete discharge of thegas charge through the cylinder head in the required time. g It will be seen that with the thimble associated with said stop member.

the head of the stopmember and the valve I closure member in the manner described, the

only manner in which the condensed refrigerant can enter the dashpot is by passing beneath the lower edge of the wall 41 into which itprojects. Any 'foreign particles passing across the groove will drop to the bottom thereof, due to their specific gravity, and therefrom theliquid which lies in the dashpot will be clean In this manner dirt will notfind its way between the contacting faces of the stop member and the valve closure member to restrict the full opening of the valve.

- The piston stroke of compressors'of the type described is rapid, and therefore I provide groove 48 in the contactingface 34 of the head of the stop member to reduce the tendency of the liquid to cause the valve closure member toadhere to the face of the stop member when being closed. Any'lag of the valve closure member so caused would permit compressed gas to flow back into the cyl inder, which would be a very undesirable condition.

It will thus be seen that the thimble element serves the three-fold function of providing a dashpot which eliminates wear and chattering of the valve closure member against the stop member, providing a hearing for thevalve closure tension spring, and assisting in preventing the entrance of dirt or grit between the contacting surfaces of {She stop member and the valve closure mem- The invention is not to be understood as restricted to the details set forth, since they may be modified within the scope of the appended claims without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a refrigerating system having a condenser in communication with the outlet port of a compressor, an exhaust valve structure comprising a seat, a closure element, a spring for exerting pressure to return and maintain said closure element against said scat between the compression strokes, a stop element to limit the lift of said closure element under a predetermined pressure, and a liquid shock absorber means associated with said closure element and sa d stop member.

2. In a refrigerating system having a condenser in communication with the outlet port of a compressor, an exhaust valve structure comprising a seat, a closure element, a spring for returning and maintaining said closure element against the seat between the compression strokes of the compressor, a spring tensioned stop element to limit the lift ofsaid closure element under a definite pressure, and a liquid containing dashpot chamber associated with said closure element and 3. In a refrigerating system having a condenser in communication with the outlet port of a compressor, an exhaust valve structure comprising aseat, a cup shaped closure element, a spring for returning and maintain-- ing said closure element against said seat between the compression strokes of said compressor, a stop element extending into said closure e ement to limit its lift under pressure, and a liquid containing thimble member seated against said closure element and enclosing the portion of said stop member with which said closure element contacts.

4. In a refrigerating system in which a condenser surrounds the outlet port of a compressor, an exhaust valve structure comprising a seat, a cup shaped closure element, a thimble member within and seated a coil spring bearing against said thimble member and exerting pressure to return said closure element to said seat after the compression stroke of the compressor, a stop member extending into said thimble and arranged to limit the lift of said closure ele ment under a predetermined pressure, said thimble being in open communication with said condenser to receive liquid refrigerant and provide a dashpot.

5. In a refrigerating system in which a condenser surrounds the head of a compressor, an exhaust valve structure comprising a seat in the head of said compressor. a cup shaped closure element, a thimble member within said closure element, a spring exerting pressure against said thimble member to return said closure element against said seat after the compression stroke of the compressor, a stop member having a head portion in spaced relation with the base of said closure member to limit thenormal lift thereof, the 11 per face ofthe head of said stop member aving an annular 'roove therein into which foreign particles in the liquid passing into said thimble will fall by gravity, said thimble having a flange extending into the groove in the head of said stop member causing liquid passing into said thimble to pass through the groove in the head of said stop member.

6. In a refrigerating system having a condenser in communication withthe outlet port of a compressor, a poppet valve associated with said compressor port and comprising a.

casing having a port and a seat, a cup shaped closure element for engaging said seat and closing said port, a thrmble member within said closure element mounted against the base of said closure element, a coil spring seated against said thimble and exerting pressure to normally seat said closure element, a movable stop member having a head portion within said closure element, said stop member being adjustable to space the head portion from the base of said closure element to permit a desired lift thereof, and a coil spring exerting pressure against the head of said stop member, said last mentioned spring being formed to exert a greater pressure than said first mentioned spring.

7. In a refrigerating system having a condenser in communication with the outlet port of a compressor, a cup shaped closure ole ment slidable in said port adapted to close the inlet end thereof, a thimble mounted within said closure element against the base thereof, a coil spring seated at one end upon said thimble and exerting pressure to seat said closure element, a movable stop member having a shank extending through said thimble and terminating in a head portion adjacent the base of said closure element,a

coil spring seated at one end against the head of said stop member a bearing for seat ing the other ends of said coil springs and arranged to compress the same axially, and

adjustable means for regulating the distance between said stop head and the base of said closure member the coil spring engaging saidlstop member exerting greater pressure than the coil spring engaging said closure element to permit said stop member to limitthe lift of said closure element under a predetermined pressure and to vpermit said stop and closure element to lift when the pressure against the closure element exceeds the predetermined amount,

8. In a refrigerating system having a condenser in communication with the outlet port of a compressor, an exhaust valve structure comprising a seat, a cup shaped closure element for engaging said seat, a movable stop member Within said closure element having a head arranged in spaced relation from the base of said closure element to limit the lift of said element under a predetermined pressure, means exerting pressure against the head of said stop member, ,a liquid containing thimble seated within said closure element and surrounding the head of said closure element, and means exerting pressure against said thimble to normally seat said closure element said stop member head having relief grooves in the contact face.

In testimony whereof, I hereunto aifix my signature JOHN R. REPLOGLE 

